Examine source code of Joyful Summer by MaDonna

{
  "name": "Joyful Summer by MaDonna",
  "manifest_version": 2,
  "version": "3.0",
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "rgba(37, 36, 41, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(39, 38, 43, 0)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(71, 69, 77, 0.06)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{10fd0728-3dfe-43fb-9c1d-37de60ec72b4}"
    }
  }
}